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PubMed2003

Relationship of gender and eating disorder symptoms to reported cravings for food: construct validation of state and trait craving questionnaires in Spanish.

Using confirmatory factor analysis, we cross-validated the factor structures of the Spanish versions of the State and Trait Food Cravings Questionnaires (FCQ-S and FCQ-T; ) in a sample of 304 Spanish college students. Controlling for eating disorder symptoms and food deprivation, scores on the FCQ-T were higher for women than for men, but no sex differences were observed on the FCQ-S. Eating disorder symptomatology was predictive of trait cravings, whereas food deprivation was predictive state cravings. Trait cravings, but not state cravings, were more strongly associated to symptoms of anorexia and bulimia nervosa than with other psychopathology. We suggest that cravings can be conceptualized as multidimensional motivational states and that our data support the hypothesis that food cravings are strongly associated with symptoms of bulimia nervosa.

Adolescent↗
PubMed2005

[Development of a questionnaire concerning the knowledge of COPD].

INTRODUCTION: The level of a patient's knowledge about his disease and its treatment is an essential part of an educational assessment. It is useful therefore to make use of a rapid, easy and valid method to collect the information necessary to develop an educational programme adapted to the needs of the patient. The aim of this study is to validate, in a structured way, a knowledge questionnaire on chronic obstructive pulmonary disease (COPD). METHODS: Following a revue of the literature an initial questionnaire was constructed. It included of four domaines: biomedical aspects; symptoms and signs of severity; general knowledge and treatments. The questionnaire was tested on 35 subjects with COPD in order to assess its clarity and comprehensibility. It was reviewed and modified in both content and format by 11: French experts. The reproducibility was studied by repeat testing. RESULTS: The first version of the questionnaire developed by the working party consisted of 50 items. It was reduced to 41 items after interviews with 35 COPD patients and evaluation by 11 experts. The questionnaire appeared to be reproducible: mean concordance 79.5%; minimum 53.3%; maximum 100% and intra-class correlation coefficient 0.53. CONCLUSION: This study lead to the development of a French language COPD knowledge questionnaire.

Adult↗
PubMed1991

Morphometrical analysis of structural abnormality of tubular tumors of the stomach with image processing.

Four indices, index of tubular density, index of dispersion of tubular size, degree of complexity of tubular shape and frequency of complex-shaped tubuli, were defined to quantify the structural abnormalities of gastric tumors in morphometrical analysis by image processing. The values of each index corresponded well with the degree of each structural abnormality found pathologically. These indices were considered to be valid for representing their respective structural factors. There were significant differences among the mean values of the scores calculated by a formula using all 4 indices of benign tubular adenoma, borderline lesion and well-differentiated type tubular adenocarcinoma (P less than 0.05). Therefore, the discriminant formula was considered to be valid for integrating these indices and for representing structural abnormality of gastric tubular tumors.

Adenocarcinoma↗
PubMed2000

The assignment and validation of metal oxidation states in the Cambridge Structural Database

A methodology has been developed for the semi-automatic assignment and checking of formal oxidation states for metal atoms in the majority of metallo-organic complexes stored in the Cambridge Structural Database (CSD). The method uses both chemical connectivity and bond-length data, via ligand donor group templates and bond-valence sums, respectively. In order to use bond-length data, the CSD program QUEST has been modified to allow the coordination sphere of metal atoms to be recalculated using user-defined criteria at search time. The new methodology has been used successfully to validate the +1, +2 and +3 oxidation states in 743 four-coordinate copper complexes in the CSD for which atomic coordinates are available in ca 99% of structures using one or other method, and both succeed for >86% of structures.

Journal Article↗
PubMed2002

Reliability and validity of combined imaging and pressures assessment methods for diabetic feet.

OBJECTIVES: To determine the reliability of using 3-dimensional (3D) spiral x-ray computed tomography (SXCT) imaging methods to measure anatomic foot structure and to test the validity of using a loading device to simulate walking pressures on the plantar foot during SXCT examination. DESIGN: Nonrandomized control trial of consecutive patients with complete data compared with age-matched controls. SETTING: A clinical SXCT scanner and physical therapy laboratory in a local hospital. PARTICIPANTS: Eight subjects with diabetes and a history of forefoot ulcers and 8 control subjects. INTERVENTIONS: SXCT imaging and plantar pressure analysis were used to acquire 3D volumetric structure and pressure data of the foot during 4 foot positions, 2 weight bearing and 2 non-weight bearing. MAIN OUTCOME MEASURES: Differences between repeated SXCT measures of foot structure. Comparisons of plantar foot pressure. Foot structure measurements. Methods for measuring the bony angles and soft-tissue thickness were developed and reliability tests were performed. RESULTS: There was essentially no bias (<+/-0.5mm or +/-0.5 degrees ) and a high degree of reliability (81% of the measures had a reliability <2.0mm or 2 degrees ) when measuring foot structures. Correlations of pressure measures collected on the loading device compared with those collected during walking were (mean +/- standard deviation) r =.66 +/-.06. The percentage agreement between the pressures collected on the loading device and during walking was 91.1% +/- 4.7%. CONCLUSION: Reliability of anatomic foot structure measurements and validity of plantar loading during visualization were good. These methods may be used to determine structural differences between diabetic and healthy feet and to evaluate how these differences relate to plantar pressures.

Adult↗
PubMed2001

Continuing medical education in a district general hospital: a snapshot.

BACKGROUND: "Consultants' continuing medical education (CME) activity is variable." Is this true? What part do prompts and constraints play? OBJECTIVE: To identify the CME activity of 80 district general hospital consultants from 27 specialties and all nine Royal Colleges. What do they do and why? What constrains them? What are their views on CME as a basis for revalidation? METHOD: A cross-sectional survey using a structured questionnaire derived from a content validity exercise, a pilot study and structured interviews. RESULTS: Of the 74 consultants who replied (92.5%) most claim to be spending sufficient time (defined by their College) undertaking a variety of internal and external CME. They do so through methods such as reading, discussion with colleagues, and teaching, which are not universally recognized by their Colleges. The majority declared most CME activity to be in their subspecialty rather than in their wider clinical or non-clinical roles. Least popular was non-clinical professional development. The majority knew how much CME they should be undertaking and all but one claimed to be doing so. Prompts were personal rather than organizational or external, while constraints centred on finding time. CME activity as a basis for re-certification was accepted and rejected by almost equal numbers. CONCLUSIONS: CME is being undertaken on the basis of personal choice. The focus is on subspecialty topics without considering needs. The guidance from the Colleges exerts little influence as a prompt. The methods chosen are personal choices and ignore what the Colleges recognize as valid CME.

Clinical Competence↗
PubMed2006

The development and initial evaluation of the survey of readiness for alcoholics anonymous participation.

This article presents 5 studies related to the development and initial evaluation of the Survey of Readiness for Alcoholics Anonymous Participation (SYRAAP). The SYRAAP is a brief, multidimensional, self-administered instrument that assesses beliefs associated with Alcoholics Anonymous (AA) participation. Study 1 generated 239 candidate items for potential inclusion in the instrument. Study 2 assessed the content validity of these items according to 3 criteria and identified a subset of 60 with the highest values on the criteria for further consideration. Study 3 produced a shorter version of the SYRAAP and evaluated its structure, internal reliability, and validity. Study 4 reevaluated the structure and internal reliability of the SYRAAP and yielded findings that were generally consistent with those from Study 3. Study 5 established stability reliability for the instrument. The collective findings indicated the SYRAAP can reliably and validly assess individual-level beliefs associated with AA participation. The potential use of the SYRAAP for researchers and clinicians, along with limitations of the work presented here, are discussed.

Adolescent↗
PubMed2002

The suitability of quality-of-life questionnaires for psoriasis research: a systematic literature review.

OBJECTIVE: To critically appraise the suitability of current quality-of-life (QOL) questionnaires for psoriasis research. DATA SOURCES: Computerized searches of 5 bibliographic databases. QUESTIONNAIRE SELECTION: Predefined criteria were used to identify QOL questionnaires in dermatologic studies. Two investigators independently assessed and agreed on multidimensional generic, dermatology-specific, and psoriasis-specific QOL questionnaires for inclusion. DATA EXTRACTION: Data were extracted on the internal structure, reliability, and validity of the included questionnaires. DATA SYNTHESIS: Three generic, 3 dermatology-specific, and none of the psoriasis-specific questionnaires met the inclusion criteria: the Nottingham Health Profile (NHP), the Medical Outcomes Study 36-Item Short Form Health Survey (SF-36), the Sickness Impact Profile (SIP), the Dermatology Quality of Life Scales (DQOLS), the Dermatology-Specific Quality of Life Instrument (DSQL), and the Skindex-29. The generic NHP, SF-36 and SIP are well established, reliable, and valid. Although the data are not conclusive, the SF-36 was useful to assess effects of psoriasis on its component scales. The dermatology-specific DQOLS, DSQL, and Skindex-29 are relatively new and, therefore, less widely tested. Available psychometric data demonstrated the reliability and validity of all 3 dermatology-specific questionnaires. The Skindex-29 was also useful to assess change. CONCLUSIONS: None of the identified psoriasis-specific questionnaires met the inclusion criteria. Data on the suitability of the included questionnaires for psoriasis research were relatively sparse. The included generic questionnaires allow comparisons with nondermatologic diseases but do not allow assessment of relevant dermatology-specific aspects and are not sensitive to subtle effects of psoriasis on QOL. On the basis of the psychometric data of the present review, we find the Skindex-29 to be the most valuable dermatology-specific questionnaire for psoriasis research. Combination of the Skindex-29 with the generic SF-36 combines the merits of both types of questionnaires and we therefore recommend this combination.

Adaptation, Psychological↗
PubMed1984

Psychological Screening Inventory: a comprehensive review.

The Psychological Screening Inventory is a relatively brief, easy to administer and score screening instrument that was designed for use by a wide range of professional mental health workers. A comprehensive review of the empirical literature suggests moderate reliability, generally stable factor structure, and adequate validity, particularly for use with college undergraduates, with reformatory and prison inmates, and with psychiatric outpatients.

Humans↗
PubMed1984

Criteria for the tracer kinetic measurement of cerebral protein synthesis in humans with positron emission tomography.

The principles and initial results of the use of PET to measure the local cerebral metabolic rate for protein synthesis ( lCRPS ) in humans are described. The labeling of leucine, phenylalanine, and methionine in the carboxyl position provides a strategy (selective position labeling) for discriminating between the incorporation of these amino acids into proteins and metabolic oxidation. In metabolic oxidation the label is removed from tissue through decarboxylation. The resulting labeled carbon dioxide is diluted by the tissue carbon dioxide pool, cleared from cerebral tissue by blood flow, and subsequently ventilated by the lungs. This approach also provides a plasma input function that is free of other labeled amino acids produced through systemic reactions, such as those that occur for methionine labeled in the methyl group. The measured lCRPS is in good agreement with values determined by Smith and Sokoloff by autoradiographic and biochemical assay techniques, as are the measured kinetic rate constants of bidirectional transport, incorporation into proteins, and metabolism, as determined in monkeys and humans using L-leucine labeled with carbon-11 in position 1 (L-[1-11C]leucine) with PET. The tissue leucine precursor pool exhibits a rapid turnover rate (1.5 to 2 minutes), while the metabolic pathway has a half-time (about 18 minutes) that is close to the radioactive half-life of carbon-11. The dietary state was found to affect the branching ratio of lCRPS /metabolism, with a fasted value of 0.4 and carbohydrate feed values ranging up to 1.7. The principle of the method appears sound, and a first-order model provides good fits to data, but much more work is required to determine and validate the model structure and to optimize the study conditions and estimation criteria.

Amino Acids↗
PubMed2005

Effects of weekly paclitaxel or paclitaxel plus carboplatin on functionality and symptoms of geriatric patients with cancer as measured by a brief geriatric oncology module: a pilot experience.

BACKGROUND: To measure functionality, symptoms, and quality of life in elderly patients, a geriatric oncology module (GOM) was developed that could be rapidly and effectively administered in community oncology practices. METHODS: The GOM was validated by semi structured patient interviews. The authors tested 26 patients receiving chemotherapy with paclitaxel or paclitaxel plus carboplatin to determine the effect of drug treatment on functionality, symptoms, and quality of life (QOL). RESULTS: Chemotherapy stabilized or improved functionality, symptoms, and QOL in 75%, 86%, and 76% of patients, respectively. This GOM was easily implemented in a busy community oncology practice. CONCLUSIONS: Weekly paclitaxel and paclitaxel plus carboplatin produced measurable palliation in geriatric oncology patients. This GOM may be useful in the assessment of specific chemotherapeutic interventions in elderly patients with cancer in community oncology practices.

Aged↗
PubMed2005

Psychometric validation of a monitoring-blunting measure for social anxiety disorder: the coping styles questionnaire for social situations (CSQSS).

The purpose of this investigation was to conduct a psychometric validation of the Coping Styles Questionnaire for Social Situations (CSQSS). The CSQSS was developed to measure monitoring and blunting coping styles in social situations based on Miller's conceptualization of how individuals cope with threat-related information. Study 1 evaluated the content validity of the CSQSS monitoring and blunting items. Study 2 examined factor structure, reliability, and construct validity of the CSQSS in a sample of 443 college students. Evidence supported the content and face validity of the CSQSS. In addition, an exploratory factor analysis revealed a two-factor solution consistent with the monitoring and blunting constructs. Both monitoring and blunting scores were positively correlated with measures of social anxiety, with blunting having a stronger relationship. Moreover, individuals with high social anxiety engaged in a significantly higher degree of monitoring and blunting than did individuals with low social anxiety. Taken together, these results provide support for the reliability and validity of the CSQSS. The CSQSS may serve as a useful measure for further examination of monitoring and blunting coping styles in a social anxiety disorder sample.

Adaptation, Psychological↗
PubMed2006

The pros and cons of change in individuals with eating disorders: a broader perspective.

OBJECTIVE: The goals of the current study were to develop a questionnaire measuring the pros and cons of eating disorder symptoms and to explore the themes endorsed by different eating disorder groups. METHOD: Participants recruited from an eating disorder volunteer register and an outpatient clinic completed the Pros and Cons of Eating Disorders scale (P-CED). Principal components analyses (PCA) were performed to validate the factorial structure of the original items and to explore the factorial structure of the new items. Planned comparisons were used to compare P-CED scores between diagnostic groups. RESULTS: PCA indicated a 10-factor solution for the original Pros and Cons of Anorexia Nervosa scale (P-CAN) items and a 4-factor solution for the new items. Participants with anorexia nervosa (AN) scored significantly higher than participants with bulimia nervosa (BN) on five of the P-CED subscales but there were no significant differences between the two AN subtypes. CONCLUSION: The P-CED is a useful tool for identifying the positive and negative aspects of eating disorders that can be targeted in treatment or used as an outcome measure in research.

Adult↗
PubMed2001

Localization of hepatitis B surface antigen epitopes present on variants and specifically recognised by anti-hepatitis B surface antigen monoclonal antibodies.

Small hepatitis B surface antigen (HBsAg) is considered to be the best marker for the diagnosis of Hepatitis B virus infection. However, HBsAg variants with mutations within the "a" determinant may be poorly or not detected by diagnostic assays. Three anti-HBsAg monoclonal antibodies (6H6B6, 27E7F10, and 2G2G10), directed against conformational epitopes, were tested for their ability to detect the wild-type HBsAg as well as variant forms and their respective epitopes were localised on the HBsAg sequence by using the phage-displayed peptide library technology. Whereas 6H6B6 did not detect mutations T123N, S143L, D144A and G145R, 27E7F10 binding was affected by mutations P120T and G145R. In contrast, 2G2G10 reacted strongly with all tested variants including variant with the G145R mutation. Part of the 6H6B6 epitope was located in the major hydrophilic region (MHR) at residues 101-105, the 27E7F10 epitope (residues 214-219) was located near the C-terminal end of the antigen and the 2G2G10 epitope at residues 199-208, within the theoretical fourth transmembrane helix. The 2G2G10 epitope localisation brings information about the HBsAg structure and the validity of established topological models. Finally, 2G2G10 is a valuable tool for HBsAg variant detection that is used as capture phase in a new bioMérieux diagnostic assay, which is currently in development.

Amino Acid Sequence↗
PubMed2003

Development and testing of the Parkinson's disease quality of life scale.

We report on the development and results of preliminary psychometric testing of a disease specific health-related quality of life (HRQoL) scale intended for use in individuals diagnosed with idiopathic Parkinson's disease (PD). Results from an initial qualitative study provided content for item development and scale construction of the Parkinson's disease quality of life scale (PDQUALIF). The 33-item instrument includes seven domains: social/role function, self-image/sexuality, sleep, outlook, physical function, independence, and urinary function, plus one item of Global HRQoL. Initial psychometric testing of the instrument was conducted in 233 outpatient clinic attendees with physician-confirmed idiopathic PD. Factor structure, reliability and validity of the scale have been established in this cross-sectional study. Continuing development of the PDQUALIF will be directed at enhancing the psychometric properties, establishing responsiveness and determining appropriateness in culturally diverse samples.

Aged↗
PubMed2006

Systematic localisation of proteins fused to the green fluorescent protein in Bacillus subtilis: identification of new proteins at the DNA replication factory.

Construction and microscopic imaging of protein fusions to green fluorescent protein (GFP) have revolutionised our understanding of bacterial structure and function. We have undertaken a systematic study of the localisation of over 100 Bacillus subtilis proteins, following the development of high-throughput construction and analysis procedures. We focused on proteins linked in various ways to the DNA replication machinery, as well as on proteins exemplifying a range of other cellular functions and structures. The results validate the approach as a way of obtaining systematic protein localisation information. They also provide a range of novel biological insights, particularly through the identification of a number of proteins not previously known to be associated with the DNA replication factory.

Bacillus subtilis↗
PubMed2007

Structural insights into the GTPase domain of Escherichia coli MnmE protein.

The Escherichia coli MnmE protein is a 50-kDa multidomain GTPase involved in tRNA modification. Its homologues in eukaryotes are crucial for mitochondrial respiration and, thus, it is thought that the human protein might be involved in mitochondrial diseases. Unlike Ras, MnmE shows a high intrinsic GTPase activity and requires effective GTP hydrolysis, and not simply GTP binding, to be functionally active. The isolated MnmE G-domain (165 residues) conserves the GTPase activity of the entire protein, suggesting that it contains the catalytic residues for GTP hydrolysis. To explore the GTP hydrolysis mechanism of MnmE, we analyzed the effect of low pH on binding and hydrolysis of GTP, as well as on the formation of a MnmE transition state mimic. GTP hydrolysis by MnmE, but not GTP binding or formation of a complex with mant-GDP and aluminium fluoride, is impaired at acidic pH, suggesting that the chemistry of the transition state mimic is different to that of the true transition state, and that some residue(s), critical for GTP hydrolysis, is severely affected by low pH. We use a nuclear magnetic resonance (NMR)-based approach to get insights into the MnmE structure and properties. The combined use of NMR restraints and homology structural information allowed the determination of the MnmE G-domain structure in its free form. Chemical shift structure-based prediction provided a good basis for structure refinement and validation. Our data support that MnmE, unlike other GTPases, does not use an arginine finger to drive catalysis, although Arg252 may play a role in stabilization of the transition state.

Amino Acid Sequence↗
PubMed1991

Comparative modeling of mammalian aspartate transcarbamylase.

Mammalian aspartate transcarbamylase (ATCase) is part of a 243 kDa multidomain polypeptide, called CAD, that catalyzes the first three steps in de novo pyrimidine biosynthesis. The structural organization of the mammalian enzyme is very different from E. coli ATCase, a dodecameric, monofunctional molecule comprised of six copies of separate catalytic and regulatory chains. Nevertheless, sequence similarities and other properties suggested that the mammalian ATCase domain and the E. coli ATCase catalytic chain have the same tertiary fold. A model of mammalian ATCase was built using the X-ray coordinates of the E. coli catalytic chain as a tertiary template. Five small insertions and deletions could be readily accommodated in the model structure. Following energy minimization the RMS difference in the alpha carbon positions of the mammalian and bacterial proteins was 0.93 A. A comparison of the hydrophobic energies, surface accessibility index, and the distribution of hydrophilic and hydrophobic residues of the CAD ATCase structure with correctly and incorrectly folded proteins and with several X-ray structures supported the validity of the model. The mammalian ATCase domain associates to form a compact globular trimer, a prerequisite for catalysis since the active site is comprised of residues from adjacent subunits. Interactions between the clearly defined aspartate and carbamyl phosphate subdomains of the monomer were largely preserved while there was appreciable remodeling of the trimeric interfaces. Several clusters of basic residues are located on the upper surface of the domain which account in part for the elevated isoelectric point (pI = 9.4) and may represent contact regions with other more acidic domains within the chimeric polypeptide. A long interdomain linker connects the monomer at its upper surface to the remainder of the polypeptide. The configuration of active site residues is virtually identical in the mammalian and bacterial enzymes. While the CAD ATCase domain can undergo the local conformational changes that accompany catalysis in the E. coli enzyme, the high activity, closed conformation is probably more stable in the mammalian enzyme.

Amino Acid Sequence↗